int main(void){
int a, b;
printf("enter two numbers;");
scanf("%d %d",&a, &b);
printf("add:%d\n",add(a, b));
printf("sub:%d\n",sub(a, b));
printf("mul:%d\n",mul(a, b));
printf("div:%lf\n",div(a, b));
return 0;
}

